Up to 80% of people with Zika virus experience no symptoms

In May 2015, the Pan American Health Organization (PAHO) issued an alert regarding the first confirmed Zika virus infection in Brazil. Then on February 1, 2016, the World Health Organization (WHO) declared Zika virus a Public Health Emergency of International Concern (PHEIC).
Zika virus disease is spread to people primarily through the bite of an infected Aedes species mosquito. The most common symptoms of Zika are fever, rash, joint pain, and conjunctivitis (red eyes). But up to 80% of people with Zika experience no symptoms and the virus can be sexually transmitted according to Manuel I. Vargas, MD, MPH, Director of the Maternal, Child and Adolescent Health Division in the Puerto Rico Department of Health. Zika virus infection during pregnancy can cause a serious birth defect called microcephaly, as well as other severe fetal brain defects.